Common variable immunodeficiency characteristic: T-cell activation, exhaled nitric oxide, and high-resolution computed tomography

Background: In adults with common variable immunodeficiency (CVID), respiratory diseases represent the main cause of morbidity and mortality. Despite adequate immunoglobulins replacement, pulmonary changes may silently progress, suggesting that an independent inflammatory mechanism might be involved. Objective: To assess airway inflammation and T-lymphocyte activation in the absence of infection in CVID patients using exhaled nitric oxide (NO) measurement, pulmonary function tests (PFT), high-resolution computed tomography (HRCT), immunological data and clinical characteristics. Methods : Data were collected retrospectively from the medical charts of 25 adults, diagnosed with CVID. T-cell activation, immunoglobulin levels, HRCT and PFT results with exhaled NO measurement were determined. Results: History of respiratory infections was present for 20 patients (80%). PFT abnormalities occurred for 60%. Forced vital capacity (FVC) and diffusing capacity of carbon monoxide (DL CO ), respectively, were significantly correlated with CD4 + HLA-DR + ( r = –0.43, p = 0.03, and r = –0.65, p = 0.002) and hypogammaglobulinemia severity ( r = 0.48, p = 0.02 and r = 0.59, p = 0.002). HRCT showed bronchial wall thickening in 13 (52%) patients and micronodules in 13 (52%) mainly centrilobular, diffuse for 8 with tree in bud appearance for 7. We observed trend associating micronodules with elevated exhaled NO ( p = 0.07). Conclusion: An HRCT pattern of centrilobular nodules and bronchial wall thickening was common in CVID patients. Significant correlations between T-lymphocyte activation and PFT parameters might suggest a role of T-cell immunity in CVID pulmonary damage.